It actually looks really nice. They've clearly upgraded the renderer a ton to support the new visuals.

I'm a bit mixed that they're upgrading the campaigns (the level they're showing off is completely different from the original) and redoing all the cutscenes (the ones they've shown look stilted, with the higher fidelity models and the old voice acting, with just basic camera angles and animations straight out of 2003). I'm not against it, but I don't know that it's really going to be an improvement.

It does sound like they plan on recreating all the cinematics, which is amazing (the upgraded teaser looked fantastic). Especially since they've been cutting way back on cinematics for their newer releases (RoS and LotV both had only a single cinematic).